1. Field of the Invention
This invention relates to a device for preventing a red-eye phenomenon occurring in flash photography.
2. Description of the Related Art
Color photographs of persons sometimes show red eyes. This is called a red-eye phenomenon. This phenomenon results from the retinal blood vessels taken in the photograph as the pupil of a person is wide open in taking a picture in a dark place with the aid of an auxiliary light such as a flash light.
To prevent the red-eye phenomenon, it has been proposed in Japanese Patent Publication No. SHO 58-48088 to carry out flash photography after making the open pupil smaller by turning on a preliminary illumination lamp prior to the emission of flash light.
The preliminary illumination by a lamp must have a relatively large degree of luminance for closing the human pupil. The sufficient degree of luminance for this purpose is hardly obtainable from the use of a small lamp but rather the use of a large lamp gives sufficient luminance. However, it not only causes a cost increase but is disadvantageous in respect of practical arrangement. A method of raising the luminance of a small lamp by condensing its light with a reflection mirror is conceivable. However, this method increases not only the cost but also the size of the camera.